Vehicle seat assemblies are usually provided with a seat adjuster for adjusting the horizontal fore and aft position of an upper track movably mounted in a lower track fixed to the vehicle and, in some cases, with a seat recliner for adjusting the angular position and height of a pivotal seat back with respect to a seat track assembly mounted on the vehicle floor. Such assemblies typically comprise a sliding mechanism to allow sliding movement of the upper track with respect to the lower track. The sliding mechanism is typically a roller, bearing, sliding sleeve, or simply mating metal sliding components.
Such structure may not have a desirable smooth sliding motion and stability of all moving components as a result of looseness due to stack up of tolerances between the mating metal components. A further problem with such structures is that they include numerous welds, rivets or threaded fasteners to hold the various metal components together, which distort the track inhibiting the smooth operation and adding substantial manufacturing costs to the assembly.
Another problem with such mating metal sliding upper and lower seat track members is the amount of noise generated by such an assembly. The power adjuster motor noise may peak due to mechanical advantage changes affecting motor operation, and the metal components tend to resonate noise from the assembly.
A further problem with typical prior art power seat adjusters is that such assemblies typically comprise around 150 to 200 different components, which results in substantial manufacturing costs.
Accordingly, it is desirable to overcome the above-referenced shortcomings of prior art power seat adjuster assemblies by reducing part count, reducing looseness of all moving components, and reducing noise of the assembly.